Abstract: The tool holder has a mounting portion (1,2) on the machine side and on the tool side and is provided with a coupling device (3) which rotationally fixedly connects the mounting portions together with a radial clearance. The coupling device includes a radially movable coupling disc (4) with two pairs of radial slots extending perpendicular to one another, axial carriers (7) on the mounting portion (1) on the machine side engaging in the one pair and axial carriers (8) on the mounting portion on the tool side engaging in the other pair. The coupling disc (4) bears on both sides on rollers which are arranged in roller cages (9) and are orientated in accordance with the perspective direction of movement.

Abstract: The tool holder, which serves principally for receiving a thread cutting tool, has a length compensation under tension and compression. This purpose is served by two compression springs which comprise massive elements of foamed, open and closed cell polyurethane elastomer. This material has good spring and damping properties. The compression springs operate without fatigue. The tool holder also has a coupling which permits radial movements of the thread cutting tool transverse to the axis of rotation in order to compensate for alignment errors.

Abstract: The invention provides a holding device for a reamer tool in a machine tool, which comprises a tool holder adapted to be secured to the machine tool for rotation about a longitudinal axis, a tool receiving bushing radially displaceably guided in the tool holder, and a coupling providing a non-rotational connection between the tool holder and the tool receiving bushing. The coupling comprises a coupling disc having two radial end faces, a first one of the coupling disc end faces cooperating with a radical end face of the tool holder, a second one of the coupling disc end faces cooperating with a radial end face of the tool receiving bushing, at least a part of the coupling disc end faces and of the tool holder and tool receiving bushing end faces being configurated as planar gliding surfaces, and pairs of the gliding surfaces facing and contacting each other for transmitting axial pushing forces to the reamer tool.